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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

41630 results found.

  1. GRB 030329: HST ACS Observations of the Host
  2. GRB 030329 Optical Observations
  3. GRB030329: XMM-Newton observation
  4. GRB 021004: HST observations
  5. GRB030324: Further Observations of the Candidate Optical Afterglow
  6. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  7. GRB 030418: Second Epoch Optical Observations with Magellan
  8. IPN triangulation of GRB030518B (annulus)
  9. HETE GRB030329, correction to Rc Observations in Loiano
  10. GRB 030329: Optical limit (contemporaneous imaging)
  11. IPN triangulation of GRB030509 (small errror box)
  12. GRB030329: RTT150 optical observations
  13. GRB030329, BVRI photometry
  14. GRB030429, refiend optical brightness
  15. GRB 030329: Optical limit (contemporaneous photography)
  16. GRB030418, BVRcIc field photometry
  17. GRB 030429: Redshift of neighbor galaxy
  18. GRB030429, BVRcIc field photometry
  19. GRB 030329: High-Resolution Spectroscopy of the Host
  20. GRB030429: RTT150 optical observations, a possible host galaxy
  21. GRB030329: RTT150 optical observations and upper limit for a host
  22. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  23. GRB030501, optical observation
  24. GRB030501 observation report
  25. GRB030329: RTT150 optical observations and upper limit for a host
  26. GRB 030429: Radio Observations
  27. GRB 030429: redshift from VLT spectroscopy
  28. GRB 030429: IR photometry with IRSF/SIRIUS
  29. GRB 030329 Optical Observations
  30. GRB030328, optical observation
  31. GRB030429: Optical Observations
  32. GRB 030501: TAROT possible candidate counterpart
  33. IPN triangulation of GRB030501 (IBIS event; annulus)
  34. GRB 030429: confirmation of afterglow candidate
  35. GRB030429, possible optical counterpart
  36. GRB030501 localized by INTEGRAL
  37. GRB030425: CrAO optical observation
  38. GRB 030329 Oprical observations in Rozhen observatory
  39. GRB 030429: ROTSE-III observations
  40. GRB 030324: Radio Observations
  41. GRB030329 observed as a sudden ionospheric disturbance (SID)
  42. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  43. IPN triangulation of GRB030425 (single error box)
  44. GRB030329, SPM optical observations (Correction)
  45. GRB030329, SPM optical observations
  46. GRB 030329, the review of the sky area in plate archive (1950-1998)
  47. GRB 030329: Spectral Evolution of SN 2003dh
  48. Optical Observations of GRB 030418 with Magellan
  49. GRB 030329: optical spectropolarimetry at VLT
  50. GRB030329: optical polarization
  51. IPN triangulation of GRB030422 (two large error boxes)
  52. GRB 030329 3.5 and 6 cm radio observations at RTF-32 telescope
  53. GRB030329, optical observation
  54. MASTER:optical observations GRB030418
  55. MASTER:optical observations probable GRB030414
  56. GRB030329: 444 AAVSO Measurements
  57. MASTER:optical observations GRB030416
  58. ROTSE-III prompt optical detections of GRB 030418
  59. GRB030418: Upper limits from recent and historical observations.
  60. GRB030418: Kiso near infrared observations
  61. GRB 030418: Optical afterglow
  62. GRB 030418: Optical afterglow candidate
  63. GRB 030329 OT position
  64. GRB030329: Optical Observations
  65. OT GRB 030329: early UBVRcIc spectral evolution
  66. GRB030329, UBVRI polarimetry, R-polarization
  67. GRB 030329: SARA Optical Observations
  68. OT GRB 030329: early spectrum
  69. GRB030329: VR Photometry at TNG
  70. GRB030324: Candidate Optical Afterglow
  71. GRB 030413: Optical Observations
  72. GRB 030329 Rc observations
  73. Superluminal motion in GRB 030329 (Correction)
  74. Superluminal motion in GRB 030329
  75. GRB 030329 and SN 2003dh
  76. GRB030329, optical position
  77. GRB 030329 VLBA Observations
  78. IPN triangulation of GRB030406 (small error box)
  79. GRB 030329: BVRI photometry at Asiago
  80. GRB 030329, light curve flattens
  81. GRB 030329: VLT V-band photometry
  82. GRB 030329: Supernova Confirmed
  83. GRB030329: RTT150 optical observations
  84. GRB030329: Near Infrared Observations at Gunma
  85. GRB030329: HET spectroscopic monitoring
  86. Kiso observation of the GRB030329 at April 6
  87. GRB 030329, color evolution
  88. GRB030328, UBVRcIc field photometry
  89. GRB030329: Optical observcations
  90. GRB030329: BV photographic observations
  91. GRB 030329 Optical observations
  92. GRB 030329, color evolution
  93. GRB 030329: possible color change
  94. GRB030329: RTT150 optical observations
  95. GRB 030329: Supernova Spectrum Emerging
  96. GRB030329: Kiso B and R band observations
  97. GRB030329: RTT150 optical observation
  98. GRB030329: More AAVSO VR obs
  99. GRB030328: R upper limit after 6 hours by MASTER
  100. GRB 030329: BV photographic observations

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